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test("labeled plain scope", () => {
notused: test: alsonotused: {
let o = 1;
expect(o).toBe(1);
unused: break test;
expect().fail();
}
});
test("break on plain scope from inner scope", () => {
notused: outer: alsonotused: {
{
unused: break outer;
}
expect().fail();
}
});
test("labeled for loop with break", () => {
let counter = 0;
notused: outer: alsonotused: for (a of [1, 2, 3]) {
for (b of [4, 5, 6]) {
if (a === 2 && b === 5) break outer;
counter++;
}
}
expect(counter).toBe(4);
});
test("labeled for loop with continue", () => {
let counter = 0;
notused: outer: alsonotused: for (a of [1, 2, 3]) {
for (b of [4, 5, 6]) {
if (b === 6) continue outer;
counter++;
}
}
expect(counter).toBe(6);
});
test("break on try catch statement", () => {
let entered = false;
label1: label2: label3: try {
entered = true;
break label2;
expect().fail();
} catch (e) {
expect().fail();
}
expect(entered).toBeTrue();
});
test("can break on every label", () => {
let i = 0;
label0: label1: label2: for (; i < 3; i++) {
block: {
break block;
expect().fail();
}
if (i === 0) continue label0;
if (i === 1) continue label1;
if (i === 2) continue label2;
expect().fail();
}
expect(i).toBe(3);
});
test("can use certain 'keywords' as labels", () => {
let i = 0;
yield: {
i++;
break yield;
expect().fail();
}
await: {
i++;
break await;
expect().fail();
}
async: {
i++;
break async;
expect().fail();
}
let: {
i++;
break let;
expect().fail();
}
// prettier-ignore
l\u0065t: {
i++;
break let;
expect().fail();
}
private: {
i++;
break private;
expect().fail();
}
expect(i).toBe(6);
expect(`const: { break const; }`).not.toEval();
});
test("can use certain 'keywords' even in strict mode", () => {
"use strict";
let i = 0;
await: {
i++;
break await;
expect().fail();
}
async: {
i++;
break async;
expect().fail();
}
expect(i).toBe(2);
expect(`'use strict'; let: { break let; }`).not.toEval();
expect(`'use strict'; l\u0065t: { break l\u0065t; }`).not.toEval();
});
test("invalid label usage", () => {
expect(() =>
eval(`
label: {
(() => {
break label;
});
}
`)
).toThrowWithMessage(SyntaxError, "Label 'label' not found");
expect(() =>
eval(`
label: {
while (false) {
continue label;
}
}
`)
).toThrowWithMessage(
SyntaxError,
"labelled continue statement cannot use non iterating statement"
);
expect(() =>
eval(`
label: label: {
break label;
}
`)
).toThrowWithMessage(SyntaxError, "Label 'label' has already been declared");
});
|
